Mark shoeld



M. SHOELD. ELECTRIC FURNACE ELECTRODE. A PPLICATlON r1120 OCT. 21. 1918.

Pateflted Aug. 12, 1919.

mm 1 M ATTORNEY UNITED STATES PATENT OFFICE.

MARK SHOELD, OF CHICAGO, ILLINOIS, ASSIGNOR TO ARMOUR FERTILIZER WORKS, OF CHICAGO, ILLINOIS, A CORPORATION OF NEW JERSEY.

ELECTRIC-FURNACE ELECTRODE.

Specification of Letters Patent.

To all whom it may concern:

Be it known'that I, MARK SHOELD, a subject of the King of Sweden, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Electric-Furnace Electrodes, of which the following is a specification.

Vertically-arranged electrodes for electric furnaces, especially those supported solely from their upper ends, are subject to breakage and other injuries in service because of their frailty' and fragility and the prime object of the present invention is to obviate these various difliculties, giving the electrodes longer life and permitting them to perform their functions more satisfactorily.

It is practically impossible toobtain single graphite electrodes of the required relativelylarge sizes needed for some furnaces, possibly due to size limitations in the production of graphite members by the ordinary and well-known processes, and the employment of the features of this invention also overcomes this difficulty. A further salient feature of the invention is the provision of an electrode of this general type which is easier to support and more readily replaced than a single large electrode would be. Other purposes of the invent-ion are to make the electrode sectional or in parts whereby if one of its elements breaks the electrode as a whole is not materially or irreparably injured, to construct the member in such a way as to expose a large surface to the mass to be treated thereby maintaining a reduced current-density at the surface of the electrode,

to provide an element of this character which causes a more uniform heating of the mass to be treated, to produce an electrode which because of its sectional character can adapt itself to reasonable warping and twisting, and to accomplish other desirable objects.

To the accomplishment of these and other ends, in the preferred embodiment of the invention, the electrode comprises a central, cylindrical element, surrounded by a plurality or set of like elements contacting therewith and with one another for mutual support and reinforcement, all of these members being individually supported at their top ends only and unitedly forming a sectional depending electrode.

In the accompanying drawing, illustrating such a desirable embodiment of the invention and throughout the various views of which like reference characters refer to the same parts, Figure l is a central, vertical section through an electric-furnace illustrating one of the improved electrodes;

Fig. 2 is a horizontal section through the electrode; and

Fig. 3 is a plan view of the central portion of the furnace showing the manner of supporting the parts of the electrode.

As is clearly illustrated in this drawing the electrode or electric terminal is composed of a central or inner cylindrical element or rod 10 of graphite or other suitable electrically-conductive material, which is usually more or less fragile and subject to breakage, supported from above only by means of a single screw 11, fastening its top end to the bottom wall of a properlysupported pan 12 adapted to contain cooling water. Grouped or arranged around this main electrode element is a plurality of like members 13, 13, six in number in the present instance, each in longitudinal line contact with the element 10 throughout their length and in a similar bearing relation with the two companion elements on opposite sides of it, whereby all of these members mutually and collectively reinforce one another and unitedly strengthen the electrode as a whole, rendering the same less subject to breakage if accidentally knocked or struck a blow. As is the case with the inclosed or central member, these outer elements are individually or separately supported at their top ends only by means of screws 14, 14 securing them to the bottom wall of the pan, each of these screws fitting in a threaded hole in the upper end of the corresponding graphite rod which it supports.

The inner, central, electrode member, except possibly at its lower face, does not necessarily come into contact with the material bein treated, which, usually in the form of briquets, passes downwardly around all sides thereof as will be readily understood and as is shown in the drawings. Its

Patented Aug. 12, 1919. l

by the united, outer, graphite rods not only increases the surface exposed as compared with a single, large, cylindrical electrode, but a more efii'cient contact is had with the briquets, the current-density at the surface of the electrode is reduced, and a more effective cooling of the electrode is possible.

By separately or individually supporting the various component parts of the electrode as a whole, it is rendered more flexible, thus permitting it to more or less readily accommodate itself to warping and twisting strains and if any element accidentally becomes broken it can be comparatively easily replaced, and in many instances successful operation can be continued until it becomes convenient to effect such repair.

Having presented in detail one desirable embodiment of the invention it is not to be understood that this is the only Wayin which the invention can be put into practical commercial form, but rather it should be appreciated that the invention is susceptible of a variety of satisfactory embodiments all incorporating the main general features and principles on which the invention' rests. For example, the rods of which the electrode is composed need not necessarily be cylindrical in cross-section, the inner one may in some cases be entirely omitted, and in other instances may be made of relatively non-conducting material.

I claim:

1. An externally longitudinally fluted or furrowed electrode for an electric furnace or the like, comprising in combination a central, vertically-disposed, cylindrical, electrically-conductive element, a plurality of vertically-disposed, parallel, cylindrical, electrically-conductive elements surrounding said central element and each in longitudinal contact with said central element and with the two outer elements on the opposite sides of itself, and means supporting said electrodes individually from their upper ends only, substantially as described.

2. An externally longitudinally fluted or furrowed electrode for an electric furnace or the like, comprising a central, cylindrical, electrically-conductive element and a plurality of parallel, cylindrical, electrically-conductive elements surrounding and in contact with said central element and each in contact with the two outer elements on the opposite sides thereof, substantially as described.

3. A longitudinally fluted or furrowed electrode for an electric furnace or the like, comprising in combination, a plurality of parallel electrically-conductive rods, and means to support said rods from their upper ends onl and in lon itudinal contact with one anot er, substantially as described.

MARK SHOELD. 

